67 



CHAPTER XIV. 



OF THE SPONDYLUS. GENUS XI. 



SPOND YL US. 



"Animal a Tethi/s. Shell strong, with unequal valves; hinge Mitii two 

 recurved teeth, separated by a small hollow." — Linn. 



1 HERE are very few species discovered yet that belong" to 

 this genus ; they somewhat resemble a Scallop in their general 

 shape, and have the connecting cartilage internal like them, 

 but differ in the beak of the lower valve, being separated from 

 that in the upper by a truncated area, and in having two 

 strong teeth in each valve, while the Scallop is without teeth ; 

 the teeth in the lov^er valve are separated by a small hollow 

 that receives the cartilage ; but the teeth in the upper valve 

 are separated by three hollows, the centre one receiving the 

 cartilage, and the other two receiving the teeth of the oppo- 

 site valve. 



Spondyhis plicatus has the beaks of the two valves ap- 

 proaching, without the truncated space that is found in some 

 others. 



The animal is a Tethys or Oyster, and has only one mascu- 

 lar impression on the inner surface of each \alve. 



LinucEus describes 3 species, Gmelin has added 1, and 

 Dr. Turton none. Total, only 4. 



K 2 



